Notify Home visibility even when DragToDesktop START aborted

The DragToDesktop START transition launches the Home task - and that's
launched through Core regardless of whether the transition is later
aborted in Shell.

Bug: 402417624
Flag: com.android.window.flags.enable_drag_to_desktop_incoming_transitions_bugfix
Test: HomeTransitionObserverTest

Change-Id: I2e629a9ed0e80152cff105ba70611e4c40b0645c